1. Field of the Invention
The invention relates to a sheet feeding apparatus and an image forming apparatus designed such that sheets stacked on sheet stacking means are brought into pressure contact with sheet feeding means by a lever operation.
2. Description of the Related Art
An image forming apparatus such as a printer or a copying machine has heretofore been provided with a sheet feeding apparatus for feeding a sheet to an image forming portion. As such a sheet feeding apparatus, there is one provided with a cassette feeding portion for feeding sheets contained in a cassette loaded on the bottom of an image forming apparatus main body, and in addition, a multi-feeding portion which is a manually feeding portion designed to stack sheets on a tray drawably or openably and closably provided in the image forming apparatus main body, and feed the sheets by a sheet feeding roller.
FIG. 12 of the accompanying drawings schematically shows the construction of a conventional image forming apparatus provided with such a multi-feeding portion, and in FIG. 12, the multi-feeding portion 140 is openably and closably provided in an image forming apparatus main body 100, and is provided with a tray 145 for stacking sheets P thereon, and a sheet feeding roller 143 rotated in conformity with an image forming operation during image forming to thereby feed the sheets P from the tray 145.
Also, a cassette feeding portion 116 is provided with a cassette 117 loaded on the bottom of the image forming apparatus main body 100, a sheet feeding roller 118 provided in the image forming apparatus main body 100 for feeding sheets P stacked on the intermediate plate 117a of the cassette 117 and a pair of retard rollers 119 for separating the sheets P one by one.
Design is made such that when the sheets P are to be fed from the multi-feeding portion 140 to an image forming portion 101, the sheets P are fed one by one from the tray 145 by the sheet feeding roller 143. Also, design is made such that when the sheets P are to be fed from the cassette feeding portion 116 to the image forming portion 101, the sheets P contained in the cassette are separated and fed one by one by the sheet feeding roller 118 and the pair of retard rollers 119. The sheets P thus fed from the multi-feeding portion 140 or the cassette feeding portion 116 are thereafter transported to the image forming portion 101, whereby images are formed thereon.
FIG. 13 of the accompanying drawings shows the construction of such a multi-feeding portion 140, and in FIG. 13, an intermediate plate 146 provided below a sheet feeding roller 143 for pivotal movement in a vertical direction is downwardly pivotally moved as shown in FIG. 14 of the accompanying drawings when the sheets are to be set on the tray 145, and by the intermediate plate 146 being thus pivotally moved, a gap “a” equal to or greater than the thickness of the sheets to be set is formed between the sheet feeding roller 143 and the intermediate plate 146.
By the gap “a” being thus formed between the sheet feeding roller 143 and the intermediate plate 146, the sheets P can be pushed into between the sheet feeding roller 143 and the intermediate plate 146. Thereafter, as shown in FIG. 15 of the accompanying drawings, the intermediate plate 146 is upwardly pivotally moved, whereby the sheets P can be brought into pressure contact with the sheet feeding roller 143, whereby when the sheet feeding roller 143 is rotated, the sheets P come to be fed out. The reference numeral 147 designates a frictional pad adapted to pressure-contact with the sheet feeding roller 143, and design is made such that the sheets P can be separated one by one by this frictional pad 147.
Now, such an intermediate plate is also provided in the cassette 117 of the cassette feeding portion 116, as shown in FIG. 12. In the cassette feeding portion 116, design is made such that when the cassette 117 is contained in the image forming apparatus main body after the sheets P have been set in the cassette 117, an intermediate plate 117a is automatically pivotally moved to a position shown in FIG. 12.
On the other hand, in the multi-feeding portion 140, it is also possible to adopt a construction similar to that of the cassette feeding portion 116, but a sheet feeding operation is possible with the tray 145 opened and therefore, with economical properties such as a manufacturing cost and a running cost further taken into account, design is made such that a lever 148 which is manually moving means shown in FIG. 16 of the accompanying drawings is manually operated in a vertical direction to thereby pivotally move the intermediate plate 146 in the vertical direction.
However, in the conventional image forming apparatus provided with the multi-feeding portion 140 designed such that the intermediate plate 146 is pivotally moved by such a lever operation, this lever 148, as shown in FIGS. 13 and 16, is disposed in opposed relationship in a direction (hereinafter referred to as the widthwise direction) orthogonal to the sheet transport direction of the tray 145, and is at a location hidden by a side regulating plate 149 for regulating the position of the sheets in the widthwise direction thereof and therefore, in some cases, a user loses sight of the lever 148.
When the user thus loses sight of the lever 148, the user forgets the lever operation, and when the user thus forgets the lever operation, for example, forgets the operation of upwardly pivotally moving the lever 148, the sheets cannot be pushed in below a sheet feeding roller 143 and therefore, faulty feeding occurs.
Also, when the user forgets the downwardly pivotally moving operation, the sheets cannot be brought into pressure contact with the sheet feeding roller 143 and therefore, even if the sheet feeding roller 143 is rotated, the sheet cannot be fed out, or cannot be fed out to the image forming portion 101 at predetermined timing.
Notes 150 are provided near the lever 148, for example, outside the sheet stacking portion 145a of the tray 145 so that the user may not forget the operation even if he notices the lever 148, but the notes 150 provided at such a location are difficult to visually perceive and in some cases, the user does not notice them. When as described above, the user forgets the lever operation even if he notices the lever 148, the sheets cannot be fed.